The present invention relates to a new and improved construction of a wedge push-in apparatus for a tensioning press or prestressing jack for a bundle of wires, wherein the wires thereof are intended to be anchored by means of wedges in an anchoring head, and for pushing-in the wedges there is provided a wedge push-in plate which can be actuated by means of lengthwise displaceable push-in elements which engage at the wedge push-in plate.
Wedge push-in apparatuses of the previously mentioned type are usually directly connected with the front end of the hydraulic tensioning press and form a unit with such press.
For the tensioning of the bundle of wires, protruding out of the concrete structure, the anchoring head together with its anchoring parts and the displaceable wedge push-in plate which is provisionally fixed in place by means of the wedges as well as a tensioning head with the tensioning wedges, are attached to the bundle of wires.
The tensioning press together with the wedge push-in apparatus are shoved by means of its anchoring parts onto the ends of the bundle of wires, and the tensioning head passes through the central opening of the tensioning- and push-in apparatus.
It is further to be mentioned that the push-in apparatus is equipped with an impact or stop flange at the inside, this stop flange serving to guide the anchoring head and to press such against the anchoring plate.
In order to actuate the wedge push-in plate there are provided push-in elements. Since these elements, on the one hand, must enable pushing through or insertion of the tensioning head, and, on the other hand, must engage over the wedge push-in plate, in order to actuate such plate for the purpose of anchoring the previously stressed or tensioned wires, the anchoring head must possess an undesirably large external diameter.